1 1 5 July 20 1 0

Darrin Polhemus Deputy Director Division of Water Quality

State Water Resources Control Board

1001 I Street Sacramento, CA 95814

Re: Effects on Water Quality of Alkylphenol Ethoxylate Surfactants (APEOs)

Dear Darrin:

In response to your June 24 request for information on APEOs, we first direct you to the letter you will have received from Rainer Hoenicke at SFEI. We have been in co ntact with Rainer and his staff and would like to acknowledge and reference their excell ent

summary on this topic , which they have kindly shared with SCCWRP staff

.

Much of the data presented in SFEI’s summary letter is consistent with what exists fr om work in Southern California. W e also agree with their assessment that very little has

been added to the literature to help with interpretation of environmental APEO

concentrations since 2008. Lastly, we concur with SFEI’s recommendation for a search

for “safer” alternatives due to the combination of APEOs high usage and apparent persistence i n receiving waters . In the remainder of this letter

, we provide additional data, information, and our own interpretation and perspective on the potential for impacts

due to this class of emerging contaminant.

Presently , we know that residues of APEOs

, which include breakdown products known

as 4

- nonylphenol (4

- NP) and 4

- octylphenol, occur in treated wastewater effluent.

Concentrations of 4

- NP in final effluent from POTWs utilizing advanced primary and full secondary treatment processes were ~1

- 2 ug/L. This compound was, however, not frequently detected at > 1 ng/L in receiving seawater, ostensibly due to the high degree of instantaneous mixing at the marine outfall locations (SCCWRP unpublished data) . We

also know that APEO residues can accumulate in marine sediments

, sometimes to parts per million levels (32 00 n g/g for 4

- nonylphenol and 39 00 n g/g for nonylphenol ethoxylates) in the Southern California Bight (Schlenk et al. 2005)

. More recent work at

these same outfall locations show concentrations to be an order of magnitude lower ( < 10 to 380 ng/g ). In contrast , very little to no APEO concentration data exist for other2

permitted discharges (e.g. stormwater runoff) or in water bodies receiving these discharges.

In contrast to the tissue s from M orro Bay as reported by SFEI, concentrations of 4

- NP in livers of hornyhead turbot ( Pl euron ichthys verticalis ) collected near large POTW marine

outfalls were similar to sediment levels (25 to 290 ng/g) (SCCWRP unpublished data)

. These findings are consistent with most other studies and provide very strong evidence

that APEOs do not biomagnify like so

- called persistent organic pollutants (e.g. DDE,

PCBs and PBDEs ) do

. As SFEI points out, the primary concern with APEOs in aquatic systems is its endo crine disrupting potential.

In the same study, several measures of chemical exposure and biological response at the

tissue and individual level for P. verticalis were determined for > 600 individuals (Bay et al. 2008)

. There was no clear outfall effect in blood plasma levels of reproductive hormones (estradiol, testosterone) or egg proteins (vitellogenin) in male fish . Moreover,

the incidence of fish intersex was virtually non

- e xistent

-- 1 of 373 male s examined

exhibited ova

- testis , one of the expecte d histological indicators associated with endocrine disruption

. The sole molecular response where a possible outfall effect was observed was for the thyroid hormone thyroxine. Lastly, the local population trends for P. verticalis based on trawl surveys at these outfalls ha ve not shown any indication of steady or

contin u ous decline. The results of this study coupled with the apparent absence of obvious effects on the biology in other California receiving waters suggests that we

ca nnot attribute effects that are likely to be associated with APEOs at their current

environmental levels directly to this class of contaminants. Due t o the lack of targeted studies on APEOs, however, w e do not have a good idea of sediment threshold levels that would be protective of aquatic marine or freshwater life, nor do we know at this time the

role of and/or potential for APEOs to modulate other modes of toxicity

. This lack of information is in part due to the complexity of APEO formulations and the resulting

absence of an economical, robust analytical methodology to characterize a broad suite of

APEO residue compound s.

RECOMMENDATIONS

 Refine and/or develop improved measurement methods for APEOs and their

residues

 Continue to m onitor APEOs and their residues in regional and pilot scale surveys

, including upcoming stormwater monitoring projects

 Initiate and carry out targeted studies to determine sediment levels where expected effects to sentinel organisms (e.g. fish) start to occur

 Share aquatic fate and toxicological information with agencies (e.g. DTSC) responsible for screening and/or approving the use of high volume chemicals3

References

Bay S et al. 2008. Effects of emerging contaminants on Southern California flatfish: synthesis and next steps. Abstract for the Society of Environmental Toxicology and Chemistry National Meeting, Tampa, FL.

Schlenk D et al. 2005. In vivo bioassay buided fractionation of m arine sediment extracts from the Southern California Bight, USA, for estrogenic activity. Environ Toxicol Chem

24:2820

- 2826.

Sincerely yours,

Keith Maruya

P r i n c i p a l S c i e n t i s t
S o u t h e r n C a l i f

o r n i a C o a s t a l W a t e r R e s e a r c h P r o j e c t
3 5 3 5 H a r b o r B o u l e v a r d S u i t e 1 1 0

C o s t a M e s a
, C A 9 2 6 2 6

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R a i n e r H o e n i c k e
, S F E I